Data radio bearer (DRB) identifier assignment for multi-radio access technology dual connectivity (MR-DC)

ABSTRACT

Methods, systems, and storage media are described for the assignment of data radio bearer (DRB) identifiers (IDs) for multi-radio access technology dual connectivity (MR-DC). Other embodiments may be described and/or claimed.

RELATED APPLICATION

The present application claims priority under 35 U.S.C. § 119 to: U.S.Provisional Application No. 62/710,312 filed Feb. 16, 2018, the contentsof which are hereby incorporated by reference in their entirety.

FIELD

Various embodiments of the present application generally relate to thefield of wireless communications, and in particular, to the assignmentof data radio bearer (DRB) identifiers (IDs) for multi-radio accesstechnology dual connectivity (MR-DC).

BACKGROUND

In long-term evolution (LTE) dual connectivity (LTE-DC) or in LTE-NRinterworking (i.e., E-UTRA-NR Dual Connectivity (EN-DC), also referredto as non-standalone architecture (NSA)), only the master node isallowed to assign an identifier (ID) (e.g., a 5 bit space) to a dataradio bearer for user equipment (UE) regardless of whether it isserviced by a master node or secondary node. In such systems, thesecondary node cannot assign a DRB ID at all. This is mainly because thesecondary node cannot establish a DRB on its own (it has to request themaster node to or be requested by the master node) and ID management byone node makes security updates less frequent (DRB ID is used as inputto the PDCP encryption algorithm). In this manner, the unique DRB IDassignment could be guaranteed for a UE.

However, in MR-DC with fifth-generation core networks (5GC), thesecondary node can establish/modify/release DRBs on its own. Among otherthings, embodiments of the present disclosure provide solutions forunique DRB ID assignment across master and secondary nodes.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will be readily understood by the following detaileddescription in conjunction with the accompanying drawings. To facilitatethis description, like reference numerals designate like structuralelements. Embodiments are illustrated by way of example and not by wayof limitation in the figures of the accompanying drawings.

FIGS. 1 and 2, 3, and 4 illustrate examples of operationflow/algorithmic structures in accordance with some embodiments.

FIG. 5 depicts an architecture of a system of a network in accordancewith some embodiments.

FIG. 6 depicts an example of components of a device in accordance withsome embodiments.

FIG. 7 depicts an example of interfaces of baseband circuitry inaccordance with some embodiments.

FIG. 8 is an illustration of a control plane protocol stack inaccordance with some embodiments.

FIG. 9 is an illustration of a user plane protocol stack in accordancewith some embodiments.

FIG. 10 illustrates components of a core network in accordance with someembodiments.

FIG. 11 is a block diagram illustrating components, according to someembodiments, of a system to support network function virtualization(NFV).

FIG. 12 depicts a block diagram illustrating components, according tosome embodiments, able to read instructions from a machine-readable orcomputer-readable medium (e.g., a non-transitory machine-readablestorage medium) and perform any one or more of the methodologiesdiscussed herein.

FIG. 13 illustrates an example of DRB ID pool modification according tovarious embodiments.

DETAILED DESCRIPTION

Embodiments discussed herein may relate to the assignment of data radiobearer (DRB) identifiers (IDs) for multi-radio access technology dualconnectivity (MR-DC). Other embodiments may be described and/or claimed.

The following detailed description refers to the accompanying drawings.The same reference numbers may be used in different drawings to identifythe same or similar elements. In the following description, for purposesof explanation and not limitation, specific details are set forth suchas particular structures, architectures, interfaces, techniques, etc.,in order to provide a thorough understanding of the various aspects ofthe claimed invention. However, it will be apparent to those skilled inthe art having the benefit of the present disclosure that the variousaspects of the invention claimed may be practiced in other examples thatdepart from these specific details. In certain instances, descriptionsof well-known devices, circuits, and methods are omitted so as not toobscure the description of the present invention with unnecessarydetail.

Various aspects of the illustrative embodiments will be described usingterms commonly employed by those skilled in the art to convey thesubstance of their work to others skilled in the art. However, it willbe apparent to those skilled in the art that alternate embodiments maybe practiced with only some of the described aspects. For purposes ofexplanation, specific numbers, materials, and configurations are setforth in order to provide a thorough understanding of the illustrativeembodiments. However, it will be apparent to one skilled in the art thatalternate embodiments may be practiced without the specific details. Inother instances, well-known features are omitted or simplified in ordernot to obscure the illustrative embodiments.

Further, various operations will be described as multiple discreteoperations, in turn, in a manner that is most helpful in understandingthe illustrative embodiments; however, the order of description shouldnot be construed as to imply that these operations are necessarily orderdependent. In particular, these operations need not be performed in theorder of presentation.

The phrase “in various embodiments,” “in some embodiments,” and the likemay refer to the same, or different, embodiments. The terms“comprising,” “having,” and “including” are synonymous, unless thecontext dictates otherwise. The phrase “A and/or B” means (A), (B), or(A and B). The phrases “A/B” and “A or B” mean (A), (B), or (A and B),similar to the phrase “A and/or B.” For the purposes of the presentdisclosure, the phrase “at least one of A and B” means (A), (B), or (Aand B). The description may use the phrases “in an embodiment,” “inembodiments,” “in some embodiments,” and/or “in various embodiments,”which may each refer to one or more of the same or differentembodiments. Furthermore, the terms “comprising,” “including,” “having,”and the like, as used with respect to embodiments of the presentdisclosure, are synonymous.

Examples of embodiments may be described as a process depicted as aflowchart, a flow diagram, a data flow diagram, a structure diagram, ora block diagram. Although a flowchart may describe the operations as asequential process, many of the operations may be performed in parallel,concurrently, or simultaneously. In addition, the order of theoperations may be re-arranged. A process may be terminated when itsoperations are completed, but may also have additional steps notincluded in the figure(s). A process may correspond to a method, afunction, a procedure, a subroutine, a subprogram, and the like. When aprocess corresponds to a function, its termination may correspond to areturn of the function to the calling function and/or the main function.

Examples of embodiments may be described in the general context ofcomputer-executable instructions, such as program code, softwaremodules, and/or functional processes, being executed by one or more ofthe aforementioned circuitry. The program code, software modules, and/orfunctional processes may include routines, programs, objects,components, data structures, etc., that perform particular tasks orimplement particular data types. The program code, software modules,and/or functional processes discussed herein may be implemented usingexisting hardware in existing communication networks. For example,program code, software modules, and/or functional processes discussedherein may be implemented using existing hardware at existing networkelements or control nodes.

DRB Identifier Assignment for MR-DC

The embodiments described herein may provide for the assignment ofunique DRB IDs across master nodes (MNs) and secondary nodes (SNs) forMR-DC. As described in more detail below, the embodiments herein maybalance the occurrence of a delay when establishing a new DRB, thesignaling exchange between MN/SN, and the risk of using the same DRB IDfrom both nodes.

In one embodiment, an MN assigns DRB IDs for all the DRBs establishedacross a MN/SN. In this embodiment, the SN requests a DRB ID whenever itwants to establish a new DRB. For example, there may be a class 1 X2/Xnprocedure (e.g., DRB ID REQUEST/RESPONSE) initiated by the SN prior toDRB establishment.

Among other things, this embodiment: does not have a risk of using thesame DRB ID from both nodes, provides more efficient ID management ifthe SN provides its currently used DRB IDs whenever requesting a DRB IDto MN, and security updates due to DRB ID wraparound can be minimal asone node is responsible for all DRB ID assignments. In this embodiment,there may be a delay and the SN signals the MN to get DRB IDs every timethe SN establishes a new DRB.

In another embodiment, DRB ID ranges may be split between the MN and SN.The MN may propose a range of DRB IDs to be used by SN so that there isno delay when establishing a new DRB (as long as there is an availableID from the range). Both nodes may negotiate range splits wheneverneeded.

In the initial SN addition for a UE, a range of DRB IDs can be providedto be used by SN (e.g. estimated based on quality of service (QoS) flowsoffloaded to SN). The SN may assign one or more DRB IDs on its own fromthe allocated pool. A node may request more IDs if it needs more DRB orwants to avoid security updates due to, for example, DRB ID wrap around(e.g. using Configuration Update procedure or a new class 1 CP procedureor UP procedure defined for the negotiation purpose). Overall, thedisjoint DRB pool is separately kept in each node and shares arere-allocated whenever one requests to the other.

Among other things, this embodiment may experience less signalingexchange compared to the previous embodiment since the signalingexchange happens only when shares are initially allocated orrenegotiated in the middle. Additionally, this embodiment may providelittle or no delay when assigning a new DRB (as long as there areavailable IDs), since a respective pool of DRB IDs is allocated for eachrespective SN to use. Furthermore, this embodiment avoids the risk ofusing the same DRB ID in both nodes.

In some cases, the estimate based on QoS flows offloaded may not beaccurate because the MN may be unaware as to how the SN manages QoS flowto DRB mapping. The wrong estimate may thus result in frequent signalingbetween the MN and SN. Additionally, security updates due to DRB IDwraparound may be more frequent than the previously-describedembodiment, as a portion of the entire DRB IDs is allocated to eachnode.

This embodiment may utilize a variety of different signalingimplementations. Some examples of such implementations include: anenumeration of the provided DRB IDs, a range by start/end similar toSCellIndex, or a single split point (if signals one DRB ID 17, then itmeans 18˜32 can be used by SN).

Embodiments of the present disclosure may help negotiate a range splitbetween an MN and an SN. For example, the initiating node may providethe DRB IDs currently used by itself, and the receiving node redesignsthe bipartition considering its own DRB IDs currently used as well.

In a simplified example, consider a DRB ID pool that is defined with a 3bit space (i.e., a total 8 DRB IDs available). In this example, the DRBID pool may be split in half, giving four DRB IDs (1, 2, 3, 4) for theMN and four DRB IDs (5, 6, 7, 8) for the SN. When the MN needs more DRBIDs, the MN can include its currently used DRB IDs in the initiatingmessage—for example, IDs 3 and 4 (assuming that IDs 1 and 2 were usedbut released).

When the SN receives the request, the SN can consider its currently usedDRB IDs (e.g., IDs 7 and 8) together with the included MN's currentlyused DRB IDs (IDs 3 and 4) to redesign the bipartition. Since IDs 3 and4 are currently used by MN, the MN's pool can further include IDs fromSN that are not currently used, and vice versa for the SN. One possibleresult of the new bipartition could thus be (3, 4, 5, 6) for the MN and(1, 2, 7, 8) for the SN.

A variety of information may be exchanged between the MN and SN (e.g.,via request and modification messages). Some examples of informationthat may be useful to achieve negotiation between MN and SN include: DRBIDs currently used; DRB IDs previously assigned but currently released(i.e., spare DRB IDs previously used by a node); DRB IDs that were neverassigned (if any); current DRB configurations; the served QoS flow orparameters; QoS flow-to-DRB mapping information; radio link quality orcondition; and/or load status or information.

In one example, the MN may propose a range of DRB IDs to be used by anSN via a secondary node addition request message (e.g., “S-NODE ADDITIONREQUEST”). In some embodiments, this message may be sent by themaster-next generation-radio access network (M-NG-RAN) node to thesecondary-next generation-radio access network (S-NG-RAN) node torequest the preparation of resources for dual connectivity operation fora specific UE.

Table 1 below shows an example of a list of available DRB IDs(“DRB_ID_Available_List” at the end of the table) in an S-NODE ADDITIONREQUEST MESSAGE. The list of available DRB IDs indicates the DRB IDsthat the S-NG-RAN node may utilize.

TABLE 1 IE type and Semantics Assigned IE/Group Name Presence Rangereference description Criticality Criticality Message Type M <reference>YES reject M-NG-RAN node M NG-RAN node Allocated at YES reject UE XnAPID UE XnAP ID the M-NG- <reference> RAN node UE Security M <reference>YES reject Capabilities SgNB M <reference> The S-KgNB which is YESreject Security Key provided by the M-NG-RAN node, see xxx. Editor'sNote: terminology “S-KgNB” to be fixed with SA3 and RAN2 S-NG-RAN nodeUE M UE Aggregate The UE Aggregate YES reject Aggregate Maximum MaximumBit Maximum Bit Rate Bit Rate Rate <reference> is split into M-NG- RANnode UE Aggregate Maximum Bit Rate and S-NG-RAN node UE AggregateMaximum Bit Rate which are enforced by M-NG-RAN node and S-NG-RAN noderespectively. Selected PLMN O PLMN The selected PLMN YES ignore Identityof the SCG in the <reference> S-NG-RAN node. Handover O <reference> YESignore Restriction List PDU sessions To 1 YES reject Be Added List >PDUsessions 1 . . . EACH reject To Be <maxnoofPDUsessions> Added Item >>PDUsession ID M <reference> — >>S-NSSAI O <reference> — >>Bearer 1 . . .EACH reject Configurations <maxnoofBearerConfigs> To Be Added >>>CHOICEBearer M Configuration >>>>SN terminated Bearer >>>>>PDU M 9.2.1.6 — —Session Setup Info - SN terminated >>>>MN terminated Bearer >>>>>PDUSession M 9.2.1.8 — — Setup Info - MN terminated M-NG-RAN node M OCTETIncludes the SCG- YES reject to S-NG-RAN STRING ConfigInfo message nodeContainer as defined in xxx Editor's Note: to be checked with RAN2S-NG-RAN node O NG-RAN node Allocated at the YES reject UE XnAP ID UEXnAP ID S-NG-RAN node <reference> Expected UE O <reference> YES ignoreBehaviour Requested MCG O ENUMERATED Indicates that YES reject splitSRBs (srb1, srb2, resources for srb1&2, . . .) MCG Split SRB arerequested. DRB ID 1 YES reject Available List >DRB ID 1 . . . EACHreject Available Item <maxnoofDRBs> IEs >>DRB ID M <reference> —

Embodiments of the present disclosure may allow the MN or SN to modifythe DRB ID pool. For example, a DRB ID Pool Modification procedure maybe performed to negotiate the bipartition of the entire DRB ID pool usedby the respective NG-RAN-NODE for the unique DRB ID assignment acrossthe M-NG-RAN-NODE and the S-NG-RAN-NODE. This procedure may useUE-associated signaling.

FIG. 13 illustrates an example of DRB ID pool modification according tovarious embodiments. As shown in this example 1300, the M-NG-RAN-NODEmay initiate the procedure by sending the DRB ID POOL MODIFICATIONREQUEST message to the S-NG-RAN-NODE. Alternatively, the S-NG-RAN-NODEmay initiate the procedure by sending the DRB ID POOL MODIFICATIONREQUEST message to the M-NG-RAN-NODE. Upon reception of the DRB ID POOLMODIFICATION REQUEST message, the receiving node replies with the DRB IDPOOL MODIFICATION RESPONSE message.

In some embodiments, the requesting node includes the DRB ID CurrentList IE within the DRB ID POOL MODIFICATION REQUEST message. Theresponding node may use this information and the currently used DRB IDsof the responding node to generate new bipartition of the entire DRB IDpool. The responding node may include the DRB ID Available List IEwithin the DRB ID POOL MODIFICATION RESPONSE message to be used as theavailable DRB IDs pool for the requesting node.

In some embodiments, the M-NG-RAN-NODE may transmit a DRB ID POOLMODIFICATION REQUEST message to the S-NG-RAN-NODE to initiate thenegotiation of DRB ID shares between MN and SN. Alternatively, theS-NG-RAN node may send the DRB ID POOL MODIFICATION REQUEST message tothe M-NG-RAN node. Table 2 below provides an example of data that may beincluded in the DRB ID POOL MODIFICATION REQUEST message.

TABLE 2 IE type and Semantics Assigned IE/Group Name Presence Rangereference description Criticality Criticality Message Type M <reference>YES reject M-NG-RAN node M NG-RAN Allocated at the YES reject UE XnAP IDnode UE M-NG-RAN node XnAP ID <reference> S-NG-RAN node M NG-RANAllocated at the YES reject UE XnAP ID node UE S-NG-RAN node XnAP ID<reference> DRB ID 1 YES reject Current List >DRB ID 1 . . . EACH rejectCurrent Item IEs <maxnoofDRBs> >>DRB ID M <reference> —

In some embodiments, the S-NG-RAN-NODE may send a DRB ID POOLMODIFICATION RESPONSE message to the M-NG-RAN-NODE to deliver the resultof the DRB ID share to be used by M-NG-RAN-NODE from the bipartition ofthe entire DRB ID pool between MN and SN. Alternatively, the S-NG-RANnode may send the DRB ID POOL MODIFICATION RESPONSE message to theM-NG-RAN node. Table 3 below provides an example of data that may beincluded in the DRB ID POOL MODIFICATION RESPONSE message.

TABLE 3 IE type and Semantics Assigned IE/Group Name Presence Rangereference description Criticality Criticality Message Type M <reference>YES reject S-NG-RAN node M NG-RAN Allocated at the YES reject UE XnAP IDnode UE S-NG-RAN node XnAP ID <reference> M-NG-RAN node M NG-RANAllocated at the YES reject UE XnAP ID node UE M-NG-RAN node XnAP ID<reference> DRB ID 1 YES reject Available List >DRB ID Avaiable 1 . . .EACH reject Item IEs <maxnoofDRBs> >>DRB ID M <reference> —

In another embodiment, each respective node may indicate the DRB IDscurrently used by the respective node other nodes (either periodicallyor whenever there is a change). This embodiment allows both master andsecondary nodes to be aware of the available DRB IDs so that a node canimmediately assign an DRB ID when establishing a new DRB without anynegotiation.

In this embodiment, a node can immediately assign an DRB ID (if any),thus providing no delay when establishing a new DRB due to the IDassignment. However, this embodiment requires a signaling exchange andthere may be a risk of using the same DRB ID between the nodes. In thisembodiment, security updates due to DRB ID wraparound can be minimizedby each node trying to use different available IDs.

In this embodiment, a node signals its peers periodically or whenever itadds or releases a DRB. In this embodiment, there may be a risk of theMN and SN using the same DRB ID if the MN and the SN assign the same DRBID at the same time before notifying each other of the assignment. Inthis embodiment, the nodes do not negotiate DRB IDs at all, rather eachnode takes whatever available on a first-come-first-serve basis.

MR-DC

Multi-Radio Access Technology (RAT) Dual Connectivity (MR-DC) mayinvolve a multiple reception (Rx)/transmission (Tx) UE that may beconfigured to utilize radio resources provided by two distinctschedulers in two different nodes connected via non-ideal backhaul, oneproviding Evolved Universal Terrestrial Radio Access (E-UTRA) access andthe other one providing NR access. One scheduler is located in a MasterNode (MN) and the other in the Secondary Node (SN). The MN and SN areconnected via a network interface and at least the MN is connected tothe core network.

MR-DC may include E-UTRA-NR Dual Connectivity (EN-DC) or NG-RANE-UTRA-NR Dual Connectivity (NGEN-DC). In EN-DC, a UE may be connectedto one evolved NodeB (eNB) that acts as an MN and one en-next generationNodeB (gNB) that acts as an SN. The eNB is connected to an evolvedpacket core (EPC) and the en-gNB is connected to the eNB via the X2interface. The en-gNB is a node that provides new radio (NR) user planeand control plane protocol terminations towards the UE, and acts as theSN in EN-DC. In NR-EN, a UE may be connected to one gNB that acts as theMN and one ng-eNB that acts as a SN. The gNB is connected to 5GC and theng-eNB (Master Node eNB) is connected to the gNB via the Xn interface.

In some embodiments, the electronic device(s), network(s), system(s),chip(s) or component(s), or portions or implementations thereof, ofFIGS. 5-12 herein may be configured to perform or execute one or moreoperation flow/algorithmic structures, processes, techniques, or methodsas described herein, or portions thereof, including the operationflow/algorithmic structures illustrated in FIGS. 1-4.

One example of an operation flow/algorithmic structure is depicted inFIG. 1, which may be performed by a master node (MN) in accordance withsome embodiments. In this example, operation flow/algorithmic structure100 may include, at 105, storing, in a memory, a list of available dataradio bearer (DRB) identifiers (IDs) usable by a secondary node (SN). Insome embodiments, the list of available DRB IDs are determined based ona quality of service (QoS) flow offloaded to the SN.

Operation flow/algorithmic structure 100 may further include, at 110generating a message that includes the list of available DRB IDs. Insome embodiments, the message may be a secondary node addition requestmessage.

Operation flow/algorithmic structure 100 may further include, at 115,transmitting or causing to transmit the message to the SN. In someembodiments, the MN may receive or cause to receive, from the SN, amodification request message comprising a list of unnecessary DRB IDsthat were previously assigned to the SN but currently released.

Another example of an operation flow/algorithmic structure is depictedin FIG. 2, which may be performed by an SN in accordance with someembodiments. In this example, operation flow/algorithmic structure 200may include, at 205, receiving or causing to receive, by an SN, amessage from a master node (MN) that includes a list of available dataradio bearer (DRB) identifiers (IDs) usable by the SN. In someembodiments, the operation flow/algorithmic structure 200 is performedby the SN. In some embodiments, the message is a secondary node additionrequest message.

Operation flow/algorithmic structure 200 may further include, at 210,storing the list of available DRB IDs in a memory. In some embodiments,the SN may generate a modification request message comprising a list ofunnecessary DRB IDs that were previously assigned to the apparatus butcurrently released; and transmit or cause to transmit the modificationrequest message to the MN. In some embodiments, the SN may allocateresources for a dual connectivity operation with a user equipment (UE)based on the list of available DRB IDs.

Another example of an operation flow/algorithmic structure is depictedin FIG. 3, which may be performed by an MN in accordance with someembodiments. In this example, operation flow/algorithmic structure 300may include, at 305, generating a message that includes a list ofavailable data radio bearer (DRB) identifiers (IDs) usable by asecondary node (SN). Operation flow/algorithmic structure 300 mayfurther include, at 310, transmitting or causing to transmit the messageto the SN. In some embodiments, the message is a secondary node additionrequest message. In some embodiments, the list of available DRB IDs aredetermined based on a quality of service (QoS) flow offloaded to the SN

Operation flow/algorithmic structure 300 may further include, at 315,receiving or causing to receive, from the SN, a modification requestmessage comprising a list of unnecessary DRB IDs that were previouslyassigned to the SN but currently released.

Another example of an operation flow/algorithmic structure is depictedin FIG. 4, which may be performed by an SN in accordance with someembodiments. In this example, operation flow/algorithmic structure 400may include, at 405, receiving or causing to receive, by a secondarynode (SN), a message from a master node (MN) that includes a list ofavailable data radio bearer (DRB) identifiers (IDs) usable by the SN. Insome embodiments, the message is a secondary node (S-NODE) additionrequest message.

Operation flow/algorithmic structure 400 may further include, at 410,allocating resources for a dual connectivity operation with a userequipment (UE) based on the list of available DRB IDs. In someembodiments, allocating the resources for the dual connectivityoperation with the user equipment (UE) includes assigning one or moreDRB IDs from the list of available DRB IDs.

Operation flow/algorithmic structure 400 may further include, at 415,performing or causing to perform a measurement for a measurement objectin FR2 using the second per-FR measurement gap pattern.

Operation flow/algorithmic structure 400 may further include, at 420,generating a modification request message comprising a list ofunnecessary DRB IDs that were previously assigned to the SN butcurrently released.

Operation flow/algorithmic structure 400 may further include, at 425,transmitting or causing to transmit the modification request message tothe MN.

FIG. 5 illustrates an architecture of a system 500 of a network inaccordance with some embodiments. The system 500 is shown to include auser equipment (UE) 501 and a UE 502. The UEs 501 and 502 areillustrated as smartphones (e.g., handheld touchscreen mobile computingdevices connectable to one or more cellular networks), but may alsocomprise any mobile or non-mobile computing device, such as PersonalData Assistants (PDAs), pagers, laptop computers, desktop computers,wireless handsets, or any computing device including a wirelesscommunications interface.

In some embodiments, any of the UEs 501 and 502 can comprise an Internetof Things (IoT) UE, which can comprise a network access layer designedfor low-power IoT applications utilizing short-lived UE connections. AnIoT UE can utilize technologies such as machine-to-machine (M2M) ormachine-type communications (MTC) for exchanging data with an MTC serveror device via a public land mobile network (PLMN), Proximity-BasedService (ProSe) or device-to-device (D2D) communication, sensornetworks, or IoT networks. The M2M or MTC exchange of data may be amachine-initiated exchange of data. An IoT network describesinterconnecting IoT UEs, which may include uniquely identifiableembedded computing devices (within the Internet infrastructure), withshort-lived connections. The IoT UEs may execute background applications(e.g., keep-alive messages, status updates, etc.) to facilitate theconnections of the IoT network.

The UEs 501 and 502 may be configured to connect, e.g., communicativelycouple, with a radio access network (RAN) 510—the RAN 510 may be, forexample, an Evolved Universal Mobile Telecommunications System (UMTS)Terrestrial Radio Access Network (E-UTRAN), a NextGen RAN (NG RAN), orsome other type of RAN. The UEs 501 and 502 utilize connections 503 and504, respectively, each of which comprises a physical communicationsinterface or layer (discussed in further detail below); in this example,the connections 503 and 504 are illustrated as an air interface toenable communicative coupling, and can be consistent with cellularcommunications protocols, such as a Global System for MobileCommunications (GSM) protocol, a code-division multiple access (CDMA)network protocol, a Push-to-Talk (PTT) protocol, a PTT over Cellular(POC) protocol, a Universal Mobile Telecommunications System (UMTS)protocol, a 3GPP Long Term Evolution (LTE) protocol, a fifth generation(5G) protocol, a New Radio (NR) protocol, and the like.

In this embodiment, the UEs 501 and 502 may further directly exchangecommunication data via a ProSe interface 505. The ProSe interface 505may alternatively be referred to as a sidelink interface comprising oneor more logical channels, including but not limited to a PhysicalSidelink Control Channel (PSCCH), a Physical Sidelink Shared Channel(PSSCH), a Physical Sidelink Discovery Channel (PSDCH), and a PhysicalSidelink Broadcast Channel (PSBCH).

The UE 502 is shown to be configured to access an access point (AP) 506via connection 507. The connection 507 can comprise a local wirelessconnection, such as a connection consistent with any IEEE 802.11protocol, wherein the AP 506 would comprise a wireless fidelity (WiFi®)router. In this example, the AP 506 is shown to be connected to theInternet without connecting to the core network of the wireless system(described in further detail below).

The RAN 510 can include one or more access nodes that enable theconnections 503 and 504. These access nodes (ANs) can be referred to asbase stations (BSs), NodeBs, evolved NodeBs (eNBs), next GenerationNodeBs (gNB), RAN nodes, and so forth, and can comprise ground stations(e.g., terrestrial access points) or satellite stations providingcoverage within a geographic area (e.g., a cell). The RAN 510 mayinclude one or more RAN nodes for providing macrocells, e.g., macro RANnode 511, and one or more RAN nodes for providing femtocells orpicocells (e.g., cells having smaller coverage areas, smaller usercapacity, or higher bandwidth compared to macrocells), e.g., low power(LP) RAN node 512.

Any of the RAN nodes 511 and 512 can terminate the air interfaceprotocol and can be the first point of contact for the UEs 501 and 502.In some embodiments, any of the RAN nodes 511 and 512 can fulfillvarious logical functions for the RAN 510 including, but not limited to,radio network controller (RNC) functions such as radio bearermanagement, uplink and downlink dynamic radio resource management anddata packet scheduling, and mobility management.

In accordance with some embodiments, the UEs 501 and 502 can beconfigured to communicate using Orthogonal Frequency-DivisionMultiplexing (OFDM) communication signals with each other or with any ofthe RAN nodes 511 and 512 over a multicarrier communication channel inaccordance various communication techniques, such as, but not limitedto, an Orthogonal Frequency-Division Multiple Access (OFDMA)communication technique (e.g., for downlink communications) or a SingleCarrier Frequency Division Multiple Access (SC-FDMA) communicationtechnique (e.g., for uplink and ProSe or sidelink communications),although the scope of the embodiments is not limited in this respect.The OFDM signals can comprise a plurality of orthogonal subcarriers.

In some embodiments, a downlink resource grid can be used for downlinktransmissions from any of the RAN nodes 511 and 512 to the UEs 501 and502, while uplink transmissions can utilize similar techniques. The gridcan be a time-frequency grid, called a resource grid or time-frequencyresource grid, which is the physical resource in the downlink in eachslot. Such a time-frequency plane representation is a common practicefor OFDM systems, which makes it intuitive for radio resourceallocation. Each column and each row of the resource grid corresponds toone OFDM symbol and one OFDM subcarrier, respectively. The duration ofthe resource grid in the time domain corresponds to one slot in a radioframe. The smallest time-frequency unit in a resource grid is denoted asa resource element. Each resource grid comprises a number of resourceblocks, which describe the mapping of certain physical channels toresource elements. Each resource block comprises a collection ofresource elements; in the frequency domain, this may represent thesmallest quantity of resources that currently can be allocated. Thereare several different physical downlink channels that are conveyed usingsuch resource blocks.

The physical downlink shared channel (PDSCH) may carry user data andhigher-layer signaling to the UEs 501 and 502. The physical downlinkcontrol channel (PDCCH) may carry information about the transport formatand resource allocations related to the PDSCH channel, among otherthings. It may also inform the UEs 501 and 502 about the transportformat, resource allocation, and H-ARQ (Hybrid Automatic Repeat Request)information related to the uplink shared channel. Typically, downlinkscheduling (assigning control and shared channel resource blocks to theUE 502 within a cell) may be performed at any of the RAN nodes 511 and512 based on channel quality information fed back from any of the UEs501 and 502. The downlink resource assignment information may be sent onthe PDCCH used for (e.g., assigned to) each of the UEs 501 and 502.

The PDCCH may use control channel elements (CCEs) to convey the controlinformation. Before being mapped to resource elements, the PDCCHcomplex-valued symbols may first be organized into quadruplets, whichmay then be permuted using a sub-block interleaver for rate matching.Each PDCCH may be transmitted using one or more of these CCEs, whereeach CCE may correspond to nine sets of four physical resource elementsknown as resource element groups (REGs). Four Quadrature Phase ShiftKeying (QPSK) symbols may be mapped to each REG. The PDCCH can betransmitted using one or more CCEs, depending on the size of thedownlink control information (DCI) and the channel condition. There canbe four or more different PDCCH formats defined in LTE with differentnumbers of CCEs (e.g., aggregation level, L=1, 2, 4, or 8).

Some embodiments may use concepts for resource allocation for controlchannel information that are an extension of the above-describedconcepts. For example, some embodiments may utilize an enhanced physicaldownlink control channel (EPDCCH) that uses PDSCH resources for controlinformation transmission. The EPDCCH may be transmitted using one ormore enhanced control channel elements (ECCEs). Similar to above, eachECCE may correspond to nine sets of four physical resource elementsknown as enhanced resource element groups (EREGs). An ECCE may haveother numbers of EREGs in some situations.

The RAN 510 is shown to be communicatively coupled to a core network(CN) 520—via an S1 interface 513. In embodiments, the CN 520 may be anevolved packet core (EPC) network, a NextGen Packet Core (NPC) network,or some other type of CN. In this embodiment, the S1 interface 513 issplit into two parts: the S1-U interface 514, which carries traffic databetween the RAN nodes 511 and 512 and the serving gateway (S-GW) 522,and the S1-mobility management entity (MME) interface 515, which is asignaling interface between the RAN nodes 511 and 512 and MMEs 521.

In this embodiment, the CN 520 comprises the MMEs 521, the S-GW 522, thePacket Data Network (PDN) Gateway (P-GW) 523, and a home subscriberserver (HSS) 524. The MMEs 521 may be similar in function to the controlplane of legacy Serving General Packet Radio Service (GPRS) SupportNodes (SGSN). The MMEs 521 may manage mobility aspects in access such asgateway selection and tracking area list management. The HSS 524 maycomprise a database for network users, including subscription-relatedinformation to support the network entities' handling of communicationsessions. The CN 520 may comprise one or several HSSs 524, depending onthe number of mobile subscribers, on the capacity of the equipment, onthe organization of the network, etc. For example, the HSS 524 canprovide support for routing/roaming, authentication, authorization,naming/addressing resolution, location dependencies, etc.

The S-GW 522 may terminate the S1 interface 513 towards the RAN 510, androutes data packets between the RAN 510 and the CN 520. In addition, theS-GW 522 may be a local mobility anchor point for inter-RAN nodehandovers and also may provide an anchor for inter-3GPP mobility. Otherresponsibilities may include lawful intercept, charging, and some policyenforcement.

The P-GW 523 may terminate an SGi interface toward a PDN. The P-GW 523may route data packets between the EPC network and external networkssuch as a network including the application server 530 (alternativelyreferred to as application function (AF)) via an Internet Protocol (IP)interface 525. Generally, the application server 530 may be an elementoffering applications that use IP bearer resources with the core network(e.g., UMTS Packet Services (PS) domain, LTE PS data services, etc.). Inthis embodiment, the P-GW 523 is shown to be communicatively coupled toan application server 530 via an IP communications interface 525. Theapplication server 530 can also be configured to support one or morecommunication services (e.g., Voice-over-Internet Protocol (VoIP)sessions, PTT sessions, group communication sessions, social networkingservices, etc.) for the UEs 501 and 502 via the CN 520.

The P-GW 523 may further be a node for policy enforcement and chargingdata collection. Policy and Charging Enforcement Function (PCRF) 526 isthe policy and charging control element of the CN 520. In a non-roamingscenario, there may be a single PCRF in the Home Public Land MobileNetwork (HPLMN) associated with a UE's Internet Protocol ConnectivityAccess Network (IP-CAN) session. In a roaming scenario with localbreakout of traffic, there may be two PCRFs associated with a UE'sIP-CAN session: a Home PCRF (H-PCRF) within a HPLMN and a Visited PCRF(V-PCRF) within a Visited Public Land Mobile Network (VPLMN). The PCRF526 may be communicatively coupled to the application server 530 via theP-GW 523. The application server 530 may signal the PCRF 526 to indicatea new service flow and select the appropriate Quality of Service (QoS)and charging parameters. The PCRF 526 may provision this rule into aPolicy and Charging Enforcement Function (PCEF) (not shown) with theappropriate traffic flow template (TFT) and QoS class of identifier(QCI), which commences the QoS and charging as specified by theapplication server 530.

FIG. 6 illustrates example components of a device 600 in accordance withsome embodiments. In some embodiments, the device 600 may includeapplication circuitry 602, baseband circuitry 604, Radio Frequency (RF)circuitry 606, front-end module (FEM) circuitry 608, one or moreantennas 610, and power management circuitry (PMC) 612 coupled togetherat least as shown. The components of the illustrated device 600 may beincluded in a UE or a RAN node. In some embodiments, the device 600 mayinclude fewer elements (e.g., a RAN node may not utilize applicationcircuitry 602, and instead include a processor/controller to process IPdata received from an EPC). In some embodiments, the device 600 mayinclude additional elements such as, for example, memory/storage,display, camera, sensor, or input/output (I/O) interface. In otherembodiments, the components described below may be included in more thanone device (e.g., said circuitries may be separately included in morethan one device for Cloud-RAN (C-RAN) implementations).

The application circuitry 602 may include one or more applicationprocessors. For example, the application circuitry 602 may includecircuitry such as, but not limited to, one or more single-core ormulti-core processors. The processor(s) may include any combination ofgeneral-purpose processors and dedicated processors (e.g., graphicsprocessors, application processors, etc.). The processors may be coupledwith or may include memory/storage and may be configured to executeinstructions stored in the memory/storage to enable various applicationsor operating systems to run on the device 600. In some embodiments,processors of application circuitry 602 may process IP data packetsreceived from an EPC.

The baseband circuitry 604 may include circuitry such as, but notlimited to, one or more single-core or multi-core processors. Thebaseband circuitry 604 may include one or more baseband processors orcontrol logic to process baseband signals received from a receive signalpath of the RF circuitry 606 and to generate baseband signals for atransmit signal path of the RF circuitry 606. Baseband processingcircuitry 604 may interface with the application circuitry 602 forgeneration and processing of the baseband signals and for controllingoperations of the RF circuitry 606. For example, in some embodiments,the baseband circuitry 604 may include a third generation (3G) basebandprocessor 604A, a fourth generation (4G) baseband processor 604B, afifth generation (5G) baseband processor 604C, or other basebandprocessor(s) 604D for other existing generations, generations indevelopment or to be developed in the future (e.g., second generation(2G), sixth generation (6G), etc.). The baseband circuitry 604 (e.g.,one or more of baseband processors 604A-D) may handle various radiocontrol functions that enable communication with one or more radionetworks via the RF circuitry 606. In other embodiments, some or all ofthe functionality of baseband processors 604A-D may be included inmodules stored in the memory 604G and executed via a Central ProcessingUnit (CPU) 604E. The radio control functions may include, but are notlimited to, signal modulation/demodulation, encoding/decoding, radiofrequency shifting, etc. In some embodiments, modulation/demodulationcircuitry of the baseband circuitry 604 may include Fast-FourierTransform (FFT), precoding, or constellation mapping/demappingfunctionality. In some embodiments, encoding/decoding circuitry of thebaseband circuitry 604 may include convolution, tail-biting convolution,turbo, Viterbi, or Low Density Parity Check (LDPC) encoder/decoderfunctionality. Embodiments of modulation/demodulation andencoder/decoder functionality are not limited to these examples and mayinclude other suitable functionality in other embodiments.

In some embodiments, the baseband circuitry 604 may include one or moreaudio digital signal processor(s) (DSP) 604F. The audio DSP(s) 604F maybe include elements for compression/decompression and echo cancellationand may include other suitable processing elements in other embodiments.Components of the baseband circuitry may be suitably combined in asingle chip, a single chipset, or disposed on a same circuit board insome embodiments. In some embodiments, some or all of the constituentcomponents of the baseband circuitry 604 and the application circuitry602 may be implemented together such as, for example, on a system on achip (SOC).

In some embodiments, the baseband circuitry 604 may provide forcommunication compatible with one or more radio technologies. Forexample, in some embodiments, the baseband circuitry 604 may supportcommunication with an evolved universal terrestrial radio access network(EUTRAN) or other wireless metropolitan area networks (WMAN), a wirelesslocal area network (WLAN), a wireless personal area network (WPAN).Embodiments in which the baseband circuitry 604 is configured to supportradio communications of more than one wireless protocol may be referredto as multi-mode baseband circuitry.

RF circuitry 606 may enable communication with wireless networks usingmodulated electromagnetic radiation through a non-solid medium. Invarious embodiments, the RF circuitry 606 may include switches, filters,amplifiers, etc. to facilitate the communication with the wirelessnetwork. RF circuitry 606 may include a receive signal path which mayinclude circuitry to down-convert RF signals received from the FEMcircuitry 608 and provide baseband signals to the baseband circuitry604. RF circuitry 606 may also include a transmit signal path which mayinclude circuitry to up-convert baseband signals provided by thebaseband circuitry 604 and provide RF output signals to the FEMcircuitry 608 for transmission.

In some embodiments, the receive signal path of the RF circuitry 606 mayinclude mixer circuitry 606 a, amplifier circuitry 606 b and filtercircuitry 606 c. In some embodiments, the transmit signal path of the RFcircuitry 606 may include filter circuitry 606 c and mixer circuitry 606a. RF circuitry 606 may also include synthesizer circuitry 606 d forsynthesizing a frequency for use by the mixer circuitry 606 a of thereceive signal path and the transmit signal path. In some embodiments,the mixer circuitry 606 a of the receive signal path may be configuredto down-convert RF signals received from the FEM circuitry 608 based onthe synthesized frequency provided by synthesizer circuitry 606 d. Theamplifier circuitry 606 b may be configured to amplify thedown-converted signals and the filter circuitry 606 c may be a low-passfilter (LPF) or band-pass filter (BPF) configured to remove unwantedsignals from the down-converted signals to generate output basebandsignals. Output baseband signals may be provided to the basebandcircuitry 604 for further processing. In some embodiments, the outputbaseband signals may be zero-frequency baseband signals, although thisis not a requirement. In some embodiments, mixer circuitry 606 a of thereceive signal path may comprise passive mixers, although the scope ofthe embodiments is not limited in this respect.

In some embodiments, the mixer circuitry 606 a of the transmit signalpath may be configured to up-convert input baseband signals based on thesynthesized frequency provided by the synthesizer circuitry 606 d togenerate RF output signals for the FEM circuitry 608. The basebandsignals may be provided by the baseband circuitry 604 and may befiltered by filter circuitry 606 c.

In some embodiments, the mixer circuitry 606 a of the receive signalpath and the mixer circuitry 606 a of the transmit signal path mayinclude two or more mixers and may be arranged for quadraturedownconversion and upconversion, respectively. In some embodiments, themixer circuitry 606 a of the receive signal path and the mixer circuitry606 a of the transmit signal path may include two or more mixers and maybe arranged for image rejection (e.g., Hartley image rejection). In someembodiments, the mixer circuitry 606 a of the receive signal path andthe mixer circuitry 606 a of the transmit signal path may be arrangedfor direct downconversion and direct upconversion, respectively. In someembodiments, the mixer circuitry 606 a of the receive signal path andthe mixer circuitry 606 a of the transmit signal path may be configuredfor super-heterodyne operation.

In some embodiments, the output baseband signals and the input basebandsignals may be analog baseband signals, although the scope of theembodiments is not limited in this respect. In some alternateembodiments, the output baseband signals and the input baseband signalsmay be digital baseband signals. In these alternate embodiments, the RFcircuitry 606 may include analog-to-digital converter (ADC) anddigital-to-analog converter (DAC) circuitry and the baseband circuitry604 may include a digital baseband interface to communicate with the RFcircuitry 606.

In some dual-mode embodiments, a separate radio IC circuitry may beprovided for processing signals for each spectrum, although the scope ofthe embodiments is not limited in this respect.

In some embodiments, the synthesizer circuitry 606 d may be afractional-N synthesizer or a fractional N/N+1 synthesizer, although thescope of the embodiments is not limited in this respect as other typesof frequency synthesizers may be suitable. For example, synthesizercircuitry 606 d may be a delta-sigma synthesizer, a frequencymultiplier, or a synthesizer comprising a phase-locked loop with afrequency divider.

The synthesizer circuitry 606 d may be configured to synthesize anoutput frequency for use by the mixer circuitry 606 a of the RFcircuitry 606 based on a frequency input and a divider control input. Insome embodiments, the synthesizer circuitry 606 d may be a fractionalN/N+1 synthesizer.

In some embodiments, frequency input may be provided by a voltagecontrolled oscillator (VCO), although that is not a requirement. Dividercontrol input may be provided by either the baseband circuitry 604 orthe applications processor 602 depending on the desired outputfrequency. In some embodiments, a divider control input (e.g., N) may bedetermined from a look-up table based on a channel indicated by theapplications processor 602.

Synthesizer circuitry 606 d of the RF circuitry 606 may include adivider, a delay-locked loop (DLL), a multiplexer and a phaseaccumulator. In some embodiments, the divider may be a dual modulusdivider (DMD) and the phase accumulator may be a digital phaseaccumulator (DPA). In some embodiments, the DMD may be configured todivide the input signal by either N or N+1 (e.g., based on a carry out)to provide a fractional division ratio. In some example embodiments, theDLL may include a set of cascaded, tunable, delay elements, a phasedetector, a charge pump and a D-type flip-flop. In these embodiments,the delay elements may be configured to break a VCO period up into Ndequal packets of phase, where Nd is the number of delay elements in thedelay line. In this way, the DLL provides negative feedback to helpensure that the total delay through the delay line is one VCO cycle.

In some embodiments, synthesizer circuitry 606 d may be configured togenerate a carrier frequency as the output frequency, while in otherembodiments, the output frequency may be a multiple of the carrierfrequency (e.g., twice the carrier frequency, four times the carrierfrequency) and used in conjunction with quadrature generator and dividercircuitry to generate multiple signals at the carrier frequency withmultiple different phases with respect to each other. In someembodiments, the output frequency may be a LO frequency (fLO). In someembodiments, the RF circuitry 606 may include an IQ/polar converter.

FEM circuitry 608 may include a receive signal path, which may includecircuitry configured to operate on RF signals received from one or moreantennas 610, amplify the received signals and provide the amplifiedversions of the received signals to the RF circuitry 606 for furtherprocessing. FEM circuitry 608 may also include a transmit signal path,which may include circuitry configured to amplify signals fortransmission provided by the RF circuitry 606 for transmission by one ormore of the one or more antennas 610. In various embodiments, theamplification through the transmit or receive signal paths may be donesolely in the RF circuitry 606, solely in the FEM 608, or in both the RFcircuitry 606 and the FEM 608.

In some embodiments, the FEM circuitry 608 may include a TX/RX switch toswitch between transmit mode and receive mode operation. The FEMcircuitry 608 may include a receive signal path and a transmit signalpath. The receive signal path of the FEM circuitry 608 may include a lownoise amplifier (LNA) to amplify received RF signals and provide theamplified received RF signals as an output (e.g., to the RF circuitry606). The transmit signal path of the FEM circuitry 608 may include apower amplifier (PA) to amplify input RF signals (e.g., provided by RFcircuitry 606), and one or more filters to generate RF signals forsubsequent transmission (e.g., by one or more of the one or moreantennas 610).

In some embodiments, the PMC 612 may manage power provided to thebaseband circuitry 604. In particular, the PMC 612 may controlpower-source selection, voltage scaling, battery charging, or DC-to-DCconversion. The PMC 612 may often be included when the device 600 iscapable of being powered by a battery, for example, when the device isincluded in a UE. The PMC 612 may increase the power conversionefficiency while providing desirable implementation size and heatdissipation characteristics.

FIG. 6 shows the PMC 612 coupled only with the baseband circuitry 604.However, in other embodiments, the PMC 612 may be additionally oralternatively coupled with, and perform similar power managementoperations for, other components such as, but not limited to,application circuitry 602, RF circuitry 606, or FEM 608.

In some embodiments, the PMC 612 may control, or otherwise be part of,various power saving mechanisms of the device 600. For example, if thedevice 600 is in an RRC_Connected state, where it is still connected tothe RAN node as it expects to receive traffic shortly, then it may entera state known as Discontinuous Reception Mode (DRX) after a period ofinactivity. During this state, the device 600 may power down for briefintervals of time and thus save power.

If there is no data traffic activity for an extended period of time,then the device 600 may transition off to an RRC_Idle state, where itdisconnects from the network and does not perform operations such aschannel quality feedback, handover, etc. The device 600 goes into a verylow power state and it performs paging where again it periodically wakesup to listen to the network and then powers down again. The device 600may not receive data in this state, in order to receive data, it musttransition back to RRC_Connected state.

An additional power saving mode may allow a device to be unavailable tothe network for periods longer than a paging interval (ranging fromseconds to a few hours). During this time, the device is totallyunreachable to the network and may power down completely. Any data sentduring this time incurs a large delay and it is assumed the delay isacceptable.

Processors of the application circuitry 602 and processors of thebaseband circuitry 604 may be used to execute elements of one or moreinstances of a protocol stack. For example, processors of the basebandcircuitry 604, alone or in combination, may be used to execute Layer 3,Layer 2, or Layer 1 functionality, while processors of the applicationcircuitry 602 may utilize data (e.g., packet data) received from theselayers and further execute Layer 4 functionality (e.g., transmissioncommunication protocol (TCP) and user datagram protocol (UDP) layers).As referred to herein, Layer 3 may comprise a radio resource control(RRC) layer, described in further detail below. As referred to herein,Layer 2 may comprise a medium access control (MAC) layer, a radio linkcontrol (RLC) layer, and a packet data convergence protocol (PDCP)layer, described in further detail below. As referred to herein, Layer 1may comprise a physical (PHY) layer of a UE/RAN node, described infurther detail below.

FIG. 7 illustrates example interfaces of baseband circuitry inaccordance with some embodiments. As discussed above, the basebandcircuitry 604 of FIG. 6 may comprise processors 604A-604E and a memory604G utilized by said processors. Each of the processors 604A-604E mayinclude a memory interface, 704A-704E, respectively, to send/receivedata to/from the memory 604G.

The baseband circuitry 604 may further include one or more interfaces tocommunicatively couple to other circuitries/devices, such as a memoryinterface 712 (e.g., an interface to send/receive data to/from memoryexternal to the baseband circuitry 604), an application circuitryinterface 714 (e.g., an interface to send/receive data to/from theapplication circuitry 602 of FIG. 6), an RF circuitry interface 716(e.g., an interface to send/receive data to/from RF circuitry 606 ofFIG. 6), a wireless hardware connectivity interface 718 (e.g., aninterface to send/receive data to/from Near Field Communication (NFC)components, Bluetooth® components (e.g., Bluetooth® Low Energy), Wi-Fi®components, and other communication components), and a power managementinterface 720 (e.g., an interface to send/receive power or controlsignals to/from the PMC 612.

FIG. 8 is an illustration of a control plane protocol stack inaccordance with some embodiments. In this embodiment, a control plane800 is shown as a communications protocol stack between the UE 501 (oralternatively, the UE 502), the RAN node 511 (or alternatively, the RANnode 512), and the MME 521.

The PHY layer 801 may transmit or receive information used by the MAClayer 802 over one or more air interfaces. The PHY layer 801 may furtherperform link adaptation or adaptive modulation and coding (AMC), powercontrol, cell search (e.g., for initial synchronization and handoverpurposes), and other measurements used by higher layers, such as the RRClayer 805. The PHY layer 801 may still further perform error detectionon the transport channels, forward error correction (FEC)coding/decoding of the transport channels, modulation/demodulation ofphysical channels, interleaving, rate matching, mapping onto physicalchannels, and Multiple Input Multiple Output (MIMO) antenna processing.

The MAC layer 802 may perform mapping between logical channels andtransport channels, multiplexing of MAC service data units (SDUs) fromone or more logical channels onto transport blocks (TB) to be deliveredto PHY via transport channels, de-multiplexing MAC SDUs to one or morelogical channels from transport blocks (TB) delivered from the PHY viatransport channels, multiplexing MAC SDUs onto TBs, schedulinginformation reporting, error correction through hybrid automatic repeatrequest (HARD), and logical channel prioritization.

The RLC layer 803 may operate in a plurality of modes of operation,including: Transparent Mode (TM), Unacknowledged Mode (UM), andAcknowledged Mode (AM). The RLC layer 803 may execute transfer of upperlayer protocol data units (PDUs), error correction through automaticrepeat request (ARQ) for AM data transfers, and concatenation,segmentation and reassembly of RLC SDUs for UM and AM data transfers.The RLC layer 803 may also execute re-segmentation of RLC data PDUs forAM data transfers, reorder RLC data PDUs for UM and AM data transfers,detect duplicate data for UM and AM data transfers, discard RLC SDUs forUM and AM data transfers, detect protocol errors for AM data transfers,and perform RLC re-establishment.

The PDCP layer 804 may execute header compression and decompression ofIP data, maintain PDCP Sequence Numbers (SNs), perform in-sequencedelivery of upper layer PDUs at re-establishment of lower layers,eliminate duplicates of lower layer SDUs at re-establishment of lowerlayers for radio bearers mapped on RLC AM, cipher and decipher controlplane data, perform integrity protection and integrity verification ofcontrol plane data, control timer-based discard of data, and performsecurity operations (e.g., ciphering, deciphering, integrity protection,integrity verification, etc.).

The main services and functions of the RRC layer 805 may includebroadcast of system information (e.g., included in Master InformationBlocks (MIBs) or System Information Blocks (SIBs) related to thenon-access stratum (NAS)), broadcast of system information related tothe access stratum (AS), paging, establishment, maintenance and releaseof an RRC connection between the UE and E-UTRAN (e.g., RRC connectionpaging, RRC connection establishment, RRC connection modification, andRRC connection release), establishment, configuration, maintenance andrelease of point to point Radio Bearers, security functions includingkey management, inter radio access technology (RAT) mobility, andmeasurement configuration for UE measurement reporting. Said MIBs andSIBs may comprise one or more information elements (IEs), which may eachcomprise individual data fields or data structures.

The UE 501 and the RAN node 511 may utilize a Uu interface (e.g., anLTE-Uu interface) to exchange control plane data via a protocol stackcomprising the PHY layer 801, the MAC layer 802, the RLC layer 803, thePDCP layer 804, and the RRC layer 805.

The non-access stratum (NAS) protocols 806 form the highest stratum ofthe control plane between the UE 501 and the MME 521. The NAS protocols806 support the mobility of the UE 501 and the session managementprocedures to establish and maintain IP connectivity between the UE 501and the P-GW 523.

The S1 Application Protocol (S1-AP) layer 815 may support the functionsof the S1 interface and comprise Elementary Procedures (EPs). An EP is aunit of interaction between the RAN node 511 and the CN 520. The S1-APlayer services may comprise two groups: UE-associated services andnon-UE-associated services. These services perform functions including,but not limited to: E-UTRAN Radio Access Bearer (E-RAB) management, UEcapability indication, mobility, NAS signaling transport, RANInformation Management (RIM), and configuration transfer.

The Stream Control Transmission Protocol (SCTP) layer (alternativelyreferred to as the SCTP/IP layer) 814 may ensure reliable delivery ofsignaling messages between the RAN node 511 and the MME 521 based, inpart, on the IP protocol, supported by the IP layer 813. The L2 layer812 and the L1 layer 811 may refer to communication links (e.g., wiredor wireless) used by the RAN node and the MME to exchange information.

The RAN node 511 and the MME 521 may utilize an S1-MME interface toexchange control plane data via a protocol stack comprising the L1 layer811, the L2 layer 812, the IP layer 813, the SCTP layer 814, and theS1-AP layer 815.

FIG. 9 is an illustration of a user plane protocol stack in accordancewith some embodiments. In this embodiment, a user plane 900 is shown asa communications protocol stack between the UE 501 (or alternatively,the UE 502), the RAN node 511 (or alternatively, the RAN node 512), theS-GW 522, and the P-GW 523. The user plane 900 may utilize at least someof the same protocol layers as the control plane 800. For example, theUE 501 and the RAN node 511 may utilize a Uu interface (e.g., an LTE-Uuinterface) to exchange user plane data via a protocol stack comprisingthe PHY layer 801, the MAC layer 802, the RLC layer 803, the PDCP layer804.

The General Packet Radio Service (GPRS) Tunneling Protocol for the userplane (GTP-U) layer 904 may be used for carrying user data within theGPRS core network and between the radio access network and the corenetwork. The user data transported can be packets in any of IPv4, IPv6,or PPP formats, for example. The UDP and IP security (UDP/IP) layer 913may provide checksums for data integrity, port numbers for addressingdifferent functions at the source and destination, and encryption andauthentication on the selected data flows. The RAN node 511 and the S-GW522 may utilize an S1-U interface to exchange user plane data via aprotocol stack comprising the L1 layer 811, the L2 layer 812, the UDP/IPlayer 913, and the GTP-U layer 904. The S-GW 522 and the P-GW 523 mayutilize an S5/S8a interface to exchange user plane data via a protocolstack comprising the L1 layer 811, the L2 layer 812, the UDP/IP layer913, and the GTP-U layer 904. As discussed above with respect to FIG. 8,NAS protocols support the mobility of the UE 501 and the sessionmanagement procedures to establish and maintain IP connectivity betweenthe UE 501 and the P-GW 523.

FIG. 10 illustrates components of a core network in accordance with someembodiments. The components of the CN 520 may be implemented in onephysical node or separate physical nodes including components to readand execute instructions from a machine-readable or computer-readablemedium (e.g., a non-transitory machine-readable storage medium). In someembodiments, Network Functions Virtualization (NFV) is utilized tovirtualize any or all of the above described network node functions viaexecutable instructions stored in one or more computer readable storagemediums (described in further detail below). A logical instantiation ofthe CN 520 may be referred to as a network slice 1001. A logicalinstantiation of a portion of the CN 520 may be referred to as a networksub-slice 1002 (e.g., the network sub-slice 1002 is shown to include thePGW 523 and the PCRF 526).

NFV architectures and infrastructures may be used to virtualize one ormore network functions, alternatively performed by proprietary hardware,onto physical resources comprising a combination of industry-standardserver hardware, storage hardware, or switches. In other words, NFVsystems can be used to execute virtual or reconfigurable implementationsof one or more EPC components/functions.

FIG. 11 is a block diagram illustrating components, according to someexample embodiments, of a system 1100 to support NFV. The system 1100 isillustrated as including a virtualized infrastructure manager (VIM)1102, a network function virtualization infrastructure (NFVI) 1104, aVNF manager (VNFM) 1106, virtualized network functions (VNFs) 1108, anelement manager (EM) 1110, an NFV Orchestrator (NFVO) 1112, and anetwork manager (NM) 1114.

The VIM 1102 manages the resources of the NFVI 1104. The NFVI 1104 caninclude physical or virtual resources and applications (includinghypervisors) used to execute the system 1100. The VIM 1102 may managethe life cycle of virtual resources with the NFVI 1104 (e.g., creation,maintenance, and tear down of virtual machines (VMs) associated with oneor more physical resources), track VM instances, track performance,fault and security of VM instances and associated physical resources,and expose VM instances and associated physical resources to othermanagement systems.

The VNFM 1106 may manage the VNFs 1108. The VNFs 1108 may be used toexecute EPC components/functions. The VNFM 1106 may manage the lifecycle of the VNFs 1108 and track performance, fault and security of thevirtual aspects of VNFs 1108. The EM 1110 may track the performance,fault and security of the functional aspects of VNFs 1108. The trackingdata from the VNFM 1106 and the EM 1110 may comprise, for example,performance measurement (PM) data used by the VIM 1102 or the NFVI 1104.Both the VNFM 1106 and the EM 1110 can scale up/down the quantity ofVNFs of the system 1100.

The NFVO 1112 may coordinate, authorize, release and engage resources ofthe NFVI 1104 in order to provide the requested service (e.g., toexecute an EPC function, component, or slice). The NM 1114 may provide apackage of end-user functions with the responsibility for the managementof a network, which may include network elements with VNFs,non-virtualized network functions, or both (management of the VNFs mayoccur via the EM 1110).

FIG. 12 is a block diagram illustrating components, according to someexample embodiments, able to read instructions from a machine-readableor computer-readable medium (e.g., a non-transitory machine-readablestorage medium) and perform any one or more of the methodologiesdiscussed herein. Specifically, FIG. 12 shows a diagrammaticrepresentation of hardware resources 1200 including one or moreprocessors (or processor cores) 1210, one or more memory/storage devices1220, and one or more communication resources 1230, each of which may becommunicatively coupled via a bus 1240. For embodiments where nodevirtualization (e.g., NFV) is utilized, a hypervisor 1202 may beexecuted to provide an execution environment for one or more networkslices/sub-slices to utilize the hardware resources 1200.

The processors 1210 (e.g., a central processing unit (CPU), a reducedinstruction set computing (RISC) processor, a complex instruction setcomputing (CISC) processor, a graphics processing unit (GPU), a digitalsignal processor (DSP) such as a baseband processor, an applicationspecific integrated circuit (ASIC), a radio-frequency integrated circuit(RFIC), another processor, or any suitable combination thereof) mayinclude, for example, a processor 1212 and a processor 1214.

The memory/storage devices 1220 may include main memory, disk storage,or any suitable combination thereof. The memory/storage devices 1220 mayinclude, but are not limited to, any type of volatile or non-volatilememory such as dynamic random access memory (DRAM), static random-accessmemory (SRAM), erasable programmable read-only memory (EPROM),electrically erasable programmable read-only memory (EEPROM), Flashmemory, solid-state storage, etc.

The communication resources 1230 may include interconnection or networkinterface components or other suitable devices to communicate with oneor more peripheral devices 1204 or one or more databases 1206 via anetwork 1208. For example, the communication resources 1230 may includewired communication components (e.g., for coupling via a UniversalSerial Bus (USB)), cellular communication components, NFC components,Bluetooth® components (e.g., Bluetooth® Low Energy), Wi-Fi® components,and other communication components.

Instructions 1250 may comprise software, a program, an application, anapplet, an app, or other executable code for causing at least any of theprocessors 1210 to perform any one or more of the methodologiesdiscussed herein. The instructions 1250 may reside, completely orpartially, within at least one of the processors 1210 (e.g., within theprocessor's cache memory), the memory/storage devices 1220, or anysuitable combination thereof. Furthermore, any portion of theinstructions 1250 may be transferred to the hardware resources 1200 fromany combination of the peripheral devices 1204 or the databases 1206.Accordingly, the memory of processors 1210, the memory/storage devices1220, the peripheral devices 1204, and the databases 1206 are examplesof computer-readable and machine-readable media.

In various embodiments, the devices/components of FIGS. 5, 6, 8, 9, 10,11, 12, and particularly the baseband circuitry of FIG. 7, may be usedfor: processing configuration information from a next-generation nodeB(gNB); determining, based on the configuration information, a type ofreference signal (RS) to be used for radio link monitoring (RLM); andperforming RLM based on the determined type of RS to be used for RLM.The devices/components of FIGS. 5-12 may also be used to practice, inwhole or in part, any of the operation flow/algorithmic structuresdepicted in FIGS. 1-4.

Examples

Some non-limiting examples are provided below.

Example 1 includes an apparatus comprising: memory to store a list ofavailable data radio bearer (DRB) identifiers (IDs) usable by asecondary node (SN); and processing circuitry, coupled with the memory,to: generate a message that includes the list of available DRB IDs; andtransmit or cause to transmit the message to the SN.

Example 2 includes the apparatus of example 1 or some other exampleherein, wherein the message is a secondary node addition requestmessage.

Example 3 includes the apparatus of example 1 or some other exampleherein, wherein the apparatus is a master node (MN).

Example 4 includes the apparatus of example 1 or some other exampleherein, wherein the processing circuitry is further to: receive or causeto receive, from the SN, a modification request message comprising alist of unnecessary DRB IDs that were previously assigned to the SN butcurrently released.

Example 5 includes the apparatus of example 1 or some other exampleherein, wherein the list of available DRB IDs are determined based on aquality of service (QoS) flow offloaded to the SN.

Example 6 includes an apparatus comprising: memory; and processingcircuitry, coupled with the memory, to: receive or cause to receive amessage from a master node (MN) that includes a list of available dataradio bearer (DRB) identifiers (IDs) usable by the apparatus; and storethe list of available DRB IDs in the memory.

Example 7 includes the apparatus of example 6 or some other exampleherein, wherein the message is a secondary node addition requestmessage.

Example 8 includes the apparatus of example 6 or some other exampleherein, wherein the apparatus is a secondary node (SN).

Example 9 includes the apparatus of example 6 or some other exampleherein, wherein the processing circuitry is further to: generate amodification request message comprising a list of unnecessary DRB IDsthat were previously assigned to the apparatus but currently released;and transmit or cause to transmit the modification request message tothe MN.

Example 10 includes the apparatus of example 6 or some other exampleherein, wherein the processing circuitry is further to allocateresources for a dual connectivity operation with a user equipment (UE)based on the list of available DRB IDs.

Example 11 includes the apparatus of example 10 or some other exampleherein, wherein allocating the resources for the dual connectivityoperation with the user equipment (UE) includes assigning one or moreDRB IDs from the list of available DRB IDs.

Example 12 includes one or more non-transitory, computer-readable mediastoring instructions, that, when executed by one or more processors,cause a master node (MN) to: generate a message that includes a list ofavailable data radio bearer (DRB) identifiers (IDs) usable by asecondary node (SN); and transmit or cause to transmit the message tothe SN.

Example 13 includes the one or more non-transitory, computer-readablemedia of example 12 or some other example herein, wherein the message isa secondary node addition request message.

Example 14 includes the one or more non-transitory, computer-readablemedia of example 12 or some other example herein, wherein the mediafurther stores instructions for causing the MN to: receive or cause toreceive, from the SN, a modification request message comprising a listof unnecessary DRB IDs that were previously assigned to the SN butcurrently released.

Example 15 includes the one or more non-transitory, computer-readablemedia of example 12 or some other example herein, wherein the list ofavailable DRB IDs are determined based on a quality of service (QoS)flow offloaded to the SN.

Example 16 includes one or more non-transitory, computer-readable mediahaving instructions that, when executed, cause a secondary node (SN) to:receive or cause to receive a message from a master node (MN) thatincludes a list of available data radio bearer (DRB) identifiers (IDs)usable by the apparatus; and allocate resources for a dual connectivityoperation with a user equipment (UE) based on the list of available DRBIDs.

Example 17 includes the one or more non-transitory, computer-readablemedia of example 16 or some other example herein, wherein the message isa secondary node (S-NODE) addition request message.

Example 18 includes the one or more non-transitory, computer-readablemedia of example 16 or some other example herein, wherein the mediafurther stores instructions for causing the SN to: generate amodification request message comprising a list of unnecessary DRB IDsthat were previously assigned to the apparatus but currently released;and transmit or cause to transmit the modification request message tothe MN.

Example 19 includes the one or more non-transitory, computer-readablemedia of example 16 or some other example herein, wherein allocating theresources for the dual connectivity operation with the user equipment(UE) includes assigning one or more DRB IDs from the list of availableDRB IDs.

Example 20 includes a method comprising: storing, in a memory, a list ofavailable data radio bearer (DRB) identifiers (IDs) usable by asecondary node (SN); generating a message that includes the list ofavailable DRB IDs; and transmitting or causing to transmit the messageto the SN.

Example 21 includes the method of example 20 or some other exampleherein, wherein the message is a secondary node addition requestmessage.

Example 22 includes the method of example 20 or some other exampleherein, wherein the method is performed by a master node (MN).

Example 23 includes the method of example 20 or some other exampleherein, further comprising: receiving or causing to receive, from theSN, a modification request message comprising a list of unnecessary DRBIDs that were previously assigned to the SN but currently released.

Example 24 includes the method of example 20 or some other exampleherein, wherein the list of available DRB IDs are determined based on aquality of service (QoS) flow offloaded to the SN.

Example 25 includes a method comprising: receiving or causing to receivea message from a master node (MN) that includes a list of available dataradio bearer (DRB) identifiers (IDs) usable by an SN; and storing thelist of available DRB IDs in a memory.

Example 26 includes the method of example 25 or some other exampleherein, wherein the message is a secondary node addition requestmessage.

Example 27 includes the method of example 25 or some other exampleherein, wherein the method is performed by the secondary node (SN).

Example 28 includes the method of example 25 or some other exampleherein, further comprising: generating a modification request messagecomprising a list of unnecessary DRB IDs that were previously assignedto the apparatus but currently released; and transmitting or causing totransmit the modification request message to the MN.

Example 29 includes the method of example 25 or some other exampleherein, further comprising allocating resources for a dual connectivityoperation with a user equipment (UE) based on the list of available DRBIDs.

Example 30 includes the method of example 29 or some other exampleherein, wherein allocating the resources for the dual connectivityoperation with the user equipment (UE) includes assigning one or moreDRB IDs from the list of available DRB IDs.

Example 31 includes a method comprising: generating, by a master node(MN) a message that includes a list of available data radio bearer (DRB)identifiers (IDs) usable by a secondary node (SN); and transmitting orcausing to transmit the message to the SN.

Example 32 includes the method of example 31 or some other exampleherein, wherein the message is a secondary node addition requestmessage.

Example 33 includes the method of example 31 or some other exampleherein, further comprising: receiving or causing to receive, from theSN, a modification request message comprising a list of unnecessary DRBIDs that were previously assigned to the SN but currently released.

Example 34 includes the method of example 31 or some other exampleherein, wherein the list of available DRB IDs are determined based on aquality of service (QoS) flow offloaded to the SN.

Example 35 includes a method comprising: receiving or causing toreceive, by a secondary node (SN), a message from a master node (MN)that includes a list of available data radio bearer (DRB) identifiers(IDs) usable by the SN; and allocating resources for a dual connectivityoperation with a user equipment (UE) based on the list of available DRBIDs.

Example 36 includes the method of example 35 or some other exampleherein, wherein the message is a secondary node (S-NODE) additionrequest message.

Example 37 includes the method of example 35 or some other exampleherein, further comprising: generating, by the SN, a modificationrequest message comprising a list of unnecessary DRB IDs that werepreviously assigned to the SN but currently released; and transmittingor causing to transmit the modification request message to the MN.

Example 38 includes the method of example 35 or some other exampleherein, wherein allocating the resources for the dual connectivityoperation with the user equipment (UE) includes assigning one or moreDRB IDs from the list of available DRB IDs.

Example 39 may include an apparatus comprising means to perform one ormore elements of a method described in or related to any of examples20-38, or any other method or process described herein.

Example 40 may include one or more non-transitory computer-readablemedia comprising instructions to cause an electronic device, uponexecution of the instructions by one or more processors of theelectronic device, to perform one or more elements of a method describedin or related to any of examples 20-38, or any other method or processdescribed herein.

Example 41 may include an apparatus comprising logic, modules, and/orcircuitry to perform one or more elements of a method described in orrelated to any of examples 20-38, or any other method or processdescribed herein.

Example 42 may include a method, technique, or process as described inor related to any of examples 20-38, or portions or parts thereof.

Example 43 may include an apparatus comprising: one or more processorsand one or more computer-readable media comprising instructions that,when executed by the one or more processors, cause the one or moreprocessors to perform the method, techniques, or process as described inor related to any of examples 20-38, or portions thereof.

Example 44 may include a method of communicating in a wireless networkas shown and described herein.

Example 45 may include a system for providing wireless communication asshown and described herein.

Example 46 may include a device for providing wireless communication asshown and described herein.

The description herein of illustrated implementations, including what isdescribed in the Abstract, is not intended to be exhaustive or to limitthe present disclosure to the precise forms disclosed. While specificimplementations and examples are described herein for illustrativepurposes, a variety of alternate or equivalent embodiments orimplementations calculated to achieve the same purposes may be made inlight of the above detailed description, without departing from thescope of the present disclosure.

What is claimed is:
 1. An apparatus comprising: memory to store a listof available data radio bearer (DRB) identifiers (IDs) usable by asecondary node (SN); and processing circuitry, coupled with the memory,to: encode a secondary node addition request message that includes thelist of available DRB IDs; send the secondary node addition requestmessage to the SN; and receive, from the SN, a modification requestmessage comprising a list of unnecessary DRB IDs that were previouslyassigned to the SN but currently released.
 2. The apparatus of claim 1,wherein the apparatus is a master node (MN).
 3. The apparatus of claim1, wherein the list of available DRB IDs are determined based on aquality of service (QoS) flow offloaded to the SN.
 4. An apparatuscomprising: memory; and processing circuitry, coupled with the memory,to: receive a secondary node addition request message from a master node(MN) that includes a list of available data radio bearer (DRB)identifiers (IDs) usable by the apparatus; store the list of availableDRB IDs in the memory; encode a modification request message comprisinga list of unnecessary DRB IDs that were previously assigned to theapparatus but currently released; and send the modification requestmessage to the MN.
 5. The apparatus of claim 4, wherein the apparatus isa secondary node (SN).
 6. The apparatus of claim 4, wherein theprocessing circuitry is further to allocate resources for a dualconnectivity operation with a user equipment (UE) based on the list ofavailable DRB IDs.
 7. The apparatus of claim 6, wherein allocating theresources for the dual connectivity operation with the user equipment(UE) includes assigning one or more DRB IDs from the list of availableDRB IDs.
 8. One or more non-transitory, computer-readable media storinginstructions, that, when executed by one or more processors, cause amaster node (MN) to: encode a secondary node addition request messagethat includes a list of available data radio bearer (DRB) identifiers(IDs) usable by a secondary node (SN); send the secondary node additionrequest message to the SN; and receive, from the SN, a modificationrequest message comprising a list of unnecessary DRB IDs that werepreviously assigned to the SN but currently released.
 9. The one or morenon-transitory, computer-readable media of claim 8, wherein the list ofavailable DRB IDs are determined based on a quality of service (QoS)flow offloaded to the SN.
 10. One or more non-transitory,computer-readable media having instructions that, when executed, cause asecondary node (SN) to: receive a secondary node addition requestmessage from a master node (MN) that includes a list of available dataradio bearer (DRB) identifiers (IDs) usable by the SN; allocateresources for a dual connectivity operation with a user equipment (UE)based on the list of available DRB IDs; encode a modification requestmessage comprising a list of unnecessary DRB IDs that were previouslyassigned to the apparatus but currently released; and send themodification request message to the MN.
 11. The one or morenon-transitory, computer-readable media of claim 10, wherein allocatingthe resources for the dual connectivity operation with the userequipment (UE) includes assigning one or more DRB IDs from the list ofavailable DRB IDs.